Next remove 3 cups of the mixture from the pot and add to a blender. Blend until completely smooth (be careful while you do this!), then transfer puree back to the pot. Stir in cooked chicken and frozen peas. Allow mixture to simmer for 5-10 more minutes to thicken up a bit. Taste and add more salt and pepper, if necessary. Garnish with extra black pepper and fresh thyme, if desired.